Effect of lung recruitment maneuver on oxygenation, physiological parameters and mortality in acute respiratory distress syndrome patients: a systematic review and meta-analysis

Purpose: Among acute respiratory distress syndrome (ARDS) patients in intensive care units, the efficacy of lung recruitment maneuver (LRM) use is uncertain taking into account the most recent randomized controlled trials (RCTs). We aimed to estimate the effect of LRMs on mortality from ARDS. Methods: In this systematic review and meta-analysis, we searched for RCTs comparing mechanical ventilation with and without LRMs in adults with ARDS. We generated pooled relative risks (RR), mean difference, performed trial-sequential-analysis and cumulative meta-analysis. The primary outcome was 28-day mortality. The secondary outcomes were oxygenation evaluated by PaO2/FiO(2) ratio, rate of rescue therapy and rate of hemodynamic compromise. Results: In 14 RCTs including 3185 patients, LRMs were not associated with reduced 28-day mortality (RR = 0.92, 95% confidence interval (95% CI) 0.82-1.04, P = 0.21), compared to no-LRM. Trial-sequential-analysis showed that the required information size has been accrued. PaO2/FiO(2) ratio was significantly higher in the LRMs group in comparison to the no-LRM group (mean difference = 47.6 mmHg, 95% CI 33.4-61.8, P < 0.001). LRMs were associated with a decreased rate of rescue therapy (RR = 0.69 95% CI 0.56-0.84, P < 0.001), and an increased rate of hemodynamic compromise (RR = 1.19, 95% CI 1.06-1.33, P = 0.002), compared to no-LRM group. Using cumulative meta-analysis, a significant change for effect on mortality was observed after 2017. Conclusions: The results suggest that in ARDS patients, systematic use of LRMs does not significantly improve 28-day mortality. However, LRM use was associated with positive effects such as an oxygenation improvement and a less frequent use of rescue therapy. Nevertheless, LRM use was associated with negative effects such as hemodynamic impairment.